1. Field of the Invention
The present invention has for its object to provide a method of information transmission in a network for data transmission over a radio channel, constituted by a central station, a fixed send station, various fixed receive stations operating in the space diversity mode and various mobile send/receive stations. The invention likewise relates to the system for which said method of information transmission is implemented.
2. Description of the Prior Art
In networks of this type data transmission over a radio channel between mobile and fixed stations poses a technical problem relating to the selection of the fixed receive station that is to present the best operation when the mobile station changes place or is located at the boundary of the zones (space-diversity reception) and thus relating to the choice of the selection criterion of the fixed station that will ensure the best reception.
The conventional solution consists of making the choice of the receive station in dependence on a criterion of the quality of a radio link, for example, using the receiver that presents the best signal-to-noise ratio, or rather selecting the receiver that presents the lowest error rate. Such a solution is known and utilized, for example, in the operating system of the Liege district bus service (Belgium).
However, implementation of this solution does have a drawback. In effect, when the mobile station changes place or when it is situated at the zone boundary, the message that is transmitted might be lost and in order to avoid losing this message, a control has to be effected to select the fixed station with respect to the changed position of the mobile station.